Potterton Suprima 50 wont turn off!! Please help!!

[cmberry20]

I hope someone here can help...

I've got the boiler as mentioned in the title & it has seemed to have locked it self in the on position.

I've turned the thermostat down to zero & turned off the control unit yet the boiler keeps going.

I've even tried another spare PCB that I had to see if it was a PCB issue (had the lock out problem last year) & it still wont turn off in to a standby state. The green light flashes all the time. I can turn the temp control on the boiler to off & the boiler does stop (flame goes off etc) but the green light carries on flashing.

So, ruling out the PCB, what can cause this the boiler to remain on?

Everything seems to be working ok. House is nice & warm & water is being heated.

Cheers.

 

[cmberry20]

Update!!

right, after checking a few things I removed the CH/HW control unit from the wall & the boiler turned off. (red light on/solid & green light off)

It seems that the control unit is sending a false signal to the boiler even when the CH/HW is set to off.

I think I need a new Control Unit.



(Anyone know where I can get a Danfoss FP15 cheaply!!)

 

[Aquaheat]

check your pm, i have some programmers available